This timeline of Russian innovation encompasses key events in the history of technology in Russia, from the Grand Duchy of Moscow up to the Russian Federation. The entries in this timeline fall into the following categories: indigenous inventions, like airliners, AC transformers, radio receivers, television, artificial satellites, ICBMs uniquely Russian products, objects and events, like Saint Basil's Cathedral, Matryoshka dolls, Russian vodka products and objects with superlative characteristics, like the Tsar Bomba, the AK-47, and the Typhoon-class submarine scientific and medical discoveries, like the periodic law, vitamins and stem cells This timeline includes scientific and medical discoveries, products and technologies introduced by various peoples of Russia and its predecessor states, regardless of ethnicity, and also lists inventions by naturalized immigrant citizens. Certain innovations achieved internationally may also appear in this timeline in cases where the Russian side played a major role in such projects. Kievan Rus' 10th century Architecture The earliest Kievan churches were built and decorated with frescoes and mosaics by Byzantine masters. The great churches of Kievan Rus', built after the adoption of Christianity in 988, were the first examples of monumental architecture in the East Slavic lands. Early Eastern Orthodox churches were mainly made of wood, while major cathedrals often featured scores of small domes. The 10th-century Church of the Tithes in Kiev was the first to be made of stone. Kokoshnik The kokoshnik is a traditional Russian head-dress for women. It is patterned to match the style of the sarafan and can be pointed or round. It is tied at the back of the head with long thick ribbons in a large bow. The forehead is sometimes decorated with pearls or other jewelry. The word kokoshnik appeared in the 16th century, however the earliest head-dress pieces of a similar type were found in the 10th to 12th century burials in Veliky Novgorod. It was worn by girls and women on special occasions until the Russian Revolution, and was subsequently introduced into Western fashion by Russian émigrés. Kvass / Okroshka Kvass or kvas, sometimes called in English a "bread drink", is a fermented beverage made from black rye or rye bread, which contributes to its light or dark colour. By the content of alcohol resulted from fermentation, it is classified as non-alcoholic: up to 1.2% of alcohol, which is so low that it is considered acceptable for consumption by children. While the early low-alcoholic prototypes of kvass